So far, Calibre as been working excellently, save for one thing it has been doing which I have not been able to figure out.

I am converting from a html page into an EPUB. Only between two endnotes (382-383) does a gap of approximately 4 lines form in the reader, despite no break being in the source html whatsoever. I have tried making the font size and style uniform throughout the entire html page, but it makes no difference-the gap still forms. What might I be overlooking or doing incorrectly?